ULTRAVIOLET STUDIES FOR ADSORPTION OF 8-QUINOLINOL ON EVAPORATED METAL FILMS

Ultraviolet spectra were obtained for 8-quinolinol adsorption on evaporated Ti, Mn, Fe, Ni, and Cu films. Each film exposed to 8-quinolinol vapor gave two bands due to adsorbed species near 240 and 265 mμ. These bands were assigned to the π-π* transitions of the quinolinol and the quinolinolate, respectively. The relative intensities of these two bands varied considerably according to the metal used, and were markedly affected by admission of air. These effects are discussed in terms of reaction properties of the metal surfaces. The spectra of the adsorbed quinolinol and quinolinolate were changed by addition of acetic acid vapor. These spectral changes were explained by considering complex formation of the adsorbed quinolinol with acetic acid by hydrogen bonding and the effect on the adsorbed quinolinolate of partial oxidation of the metal films during acetic acid adsorption.